Infection-Preventing Gastrostomy Catheter Kit for Gastrostomy

ABSTRACT

An infection-preventing gastrostomy catheter kit to be used in the gastrostomy, which can pass an intragastric retainer of a catheter easily and reliably through an infection-preventing sheath by an easy maneuver, and which can reduce the diameter of the infection-preventing sheath. 
     The catheter kit comprises: a gastrostomy catheter  20  including a flexible, hollow PEG tube  21  reinforced with filaments  24,  an deformable intragastric retainer  23  positioned at the trailing end of the PEG tube  21,  and a tapered member  22  positioned at the leading end of the PEG tube  21  for retaining the leading end portion  40   a  of a guide wire  40  inserted from a leading end hole  22   a  thereof; and an infection-preventing sheath  1  including a flexible, hollow tubular body  2,  and a socket member having a socket  4  positioned at the trailing end of the tubular body  2  for retaining the intragastric retainer  23,  and pins  5,  thereby removably sheathing the gastrostomy catheter  20.  The gastrostomy catheter  20  may be provided with a housing sheath  60  for deforming and housing the intragastric retainer  23.

TECHNICAL FIELD

The present invention relates to an infection-preventing gastrostomycatheter kit for gastrostomy, to prevent a stoma infection.

BACKGROUND ART

An infection-preventing gastrostomy kit can retain a catheter withoutinfecting a stoma when a gastrostomy operation is executed through anendoscope. This infection-preventing gastrostomy kit comprises: acatheter having a stopper at its trailing end, and fixed through anabdominal wall between the stomach cavity and the outside of the body;an over tube that is adapted to be inserted for introducing the catheterinto the stomach cavity; and a soft cover disposed in the hole of theover tube. The outer circumferential wall of the leading end of the overtube on the inserted side is sheathed by folding back the trailing endof the soft cover. Another terminal end of the soft cover extrudes fromthe root end of the over tube (as referred to in Patent Publication 1,for example).

[Patent Publication 1]

JP-A-2003-275324 (page 1, FIG. 1 to FIG. 13)

DISCLOSURE OF THE INVENTION

According to the infection-preventing gastrostomy kit of the prior art,the catheter and the stopper experience a high resistance when they passthrough the over tube. On the other hand, the patient has to accept thethick over tube that is inserted. As a result, the pains of the patientare not sufficiently relieved.

The invention has been conceived to solve the problems described above,and has as an object to provide an infection-preventing gastrostomycatheter kit to be used in the gastrostomy, which can pass anintragastric retainer of a catheter easily and reliably through aninfection-preventing sheath by an easy maneuver and which can reduce thediameter of the infection-preventing sheath.

According to the invention, there is provided an infection-preventingsheath gastrostomy catheter kit comprising: a gastrostomy catheterincluding a flexible, hollow tube reinforced with filaments, adeformable intragastric retainer positioned at the trailing end of thetube, and a tapered member positioned at the leading end of the tube forretaining the leading end portion of a guide wire inserted from theleading end hole thereof; and an infection-preventing sheath including aflexible, hollow tubular body, and a socket member positioned at thetrailing end of the tubular body for retaining the intragastricretainer, to sheathe the gastrostomy catheter removably.

There is also provided an infection-preventing sheath gastrostomycatheter kit comprising: a gastrostomy catheter including a flexible,hollow tube reinforced with filaments, a deformable intragastricretainer positioned at the trailing end of the tube, a tapered memberpositioned at the leading end of the tube for retaining the leading endportion of a guide wire inserted from the leading end hole thereof, anda housing sheath for deforming and housing the intragastric retainer;and an infection-preventing sheath including a flexible, hollow tubularbody, and a socket member positioned at the trailing end of the tubularbody for retaining the intragastric retainer, thereby to sheathe thegastrostomy catheter removably.

In this case, the infection-preventing sheath may further include a hookmember disposed near the leading end portion of its inner wall forhooking the housing sheath.

The housing sheath may be made of a slender, hollow, flexible tubularbody.

Moreover, the gastrostomy catheter is provided with filaments at itsthick portion.

In this case, the filaments may be disposed generally parallel to thelongitudinal direction of the thick portion of the gastrostomy catheter.

On the other hand, the filaments may be buried generally in parallelwith the longitudinal direction of the thick portion of the gastrostomycatheter.

Moreover, the filaments may be buried at a predetermined spacing in thecircumferential direction of the thick portion of the gastrostomycatheter.

On the other hand, the filaments may be made of wires of stainlesssteel.

The filaments may have an external diameter of about 0.2 mm.

Moreover, the intragastric retainer is foldable and deformable.

The resistance to the passage at the time when the intragastric retainerpasses through the infection-preventing sheath, and an invasion to thepatient and a burden on the doctor can be reduced by thinning a tubularbody or an infection-preventing sheath. Moreover, the maneuver can besimplified to enable even an inexperienced doctor to operate thegastrostomy easily.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an infection-preventing sheath accordingto Embodiment 1 of the Invention;

FIG. 2 is a perspective view of a catheter for gastrostomy;

FIGS. 3( a)-(b) present a sectional view and a side view of an essentialportion of FIG. 2;

FIGS. 4( a)-(c) present diagrams to explain the steps for views of FIG.2;

FIG. 5 is a side view of an essential portion of FIG. 4;

FIG. 6 is a top plan view of FIG. 5;

FIG. 7 is an explanatory view of an essential portion of FIG. 1;

FIG. 8 is a diagram for explaining the steps of a gastrostomy methodaccording to Embodiment 1;

FIG. 9 is a diagram for explaining the steps of the gastrostomy methodaccording to Embodiment 1;

FIG. 10 is a diagram for explaining the steps of the gastrostomy methodaccording to Embodiment 1;

FIG. 11 is a diagram for explaining the steps of the gastrostomy methodaccording to Embodiment 1;

FIG. 12 is a diagram for explaining the steps of the gastrostomy methodaccording Embodiment 1;

FIG. 13 is a diagram for explaining the steps of the gastrostomy methodaccording Embodiment 1;

FIG. 14 is a diagram for explaining the steps of the gastrostomy methodaccording Embodiment 1;

FIG. 15 is a diagram for explaining the steps of the gastrostomy methodaccording Embodiment 1;

FIG. 16 is a side elevation showing an infection-preventing gastrostomycatheter kit according to Embodiment 2 of the invention;

FIG. 17 is a diagram for explaining the steps of FIG. 16;

FIG. 18 is a diagram for explaining the steps of FIG. 16; and

FIG. 19 is a diagram for explaining the steps of a gastrostomy methodaccording to Embodiment 2.

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1

FIG. 1 is a perspective view showing an inspection preventinggastrostomy catheter kit to be used in an inspection-preventinggastrostomy method (as will be called the “PEG method”), and FIG. 2 is aperspective view showing a gastrostomy catheter (as will be called the“PEG catheter”). An inspection-preventing sheath 1 removably sheathesthe PEG catheter 20 (which will be described in detail) from its outerside, thereby preventing the PEG catheter 20 from being contaminatedwith bacteria in an oral cavity, a pharynx or a larynx. Theinspection-preventing sheath 1 includes a slender, hollow flexibletubular body 2, which can also be called the “flexible tubular member”or “flexible tube”. A leading end thin film 3, which is cut at itsleading end, is fixed to the leading end of the tubular body 2. A hollowsocket 4 is disposed at the trailing end of the tubular body 2. Thesocket 4 has a generally frusto-conical portion and a generallycylindrical portion leading to an end portion on the radially largerside of the frusto-conical portion. The socket 4 is formed to have itsradially smaller end portion mouth adhered to the trailing end of thetubular body 2 with an adhesive or the like, or fused to or moldedintegrally with the same. The opposed portions of the cylindricalportion of the socket 4 have drilled bearing holes 4 a, in which pins 5are to be inserted. Here, the cylindrical portion may be constructed tosheathe an intragastric retainer, or may be constructed not to sheaththe same.

The tubular body 2 is made of a flexible, strong material of polyvinylchloride that has gas-tightness, water-tightness and no shrinkage in thelongitudinal direction. The tubular body 2 is preferably cylindrical,but may alternatively have a shape of a flattened section, such as anelliptical shape. The socket 4 is made of a hard material such aspolycarbonate, and the leading end film 3 is made of a thin sheet ofpolyvinyl chloride or the like.

The PEG catheter 20 is constructed by continuously integrating: aslender, hollow PEG tube 21; a tapered member 22 disposed at the leadingend of the PEG tube 21, tapered generally conically toward its leadingend and provided with a hole 22 a leading to the hollow inside of thePEG tube 21; and an intragastric retainer 23 positioned at the trailingend. The PEG tube 21 is made of a resilient material such aspolyurethane. The tapered member 22 is made of a relatively hardmaterial such as polypropylene, and the intragastric retainer 23 is madeof a flexible material such as polyurethane having such an elasticitydeformable by an external force and restored to its original shape whenthe external force disappears.

The PEG tube 21 is provided, as shown in FIGS. 3( a)-(b), with aplurality of hardly extensible filaments 24 in the longitudinaldirection of a thick portion 21 a. More specifically, the filaments 24are arrayed at a predetermined interval along the circumferentialdirection of the thick portion 21 a and generally in parallel in thelongitudinal direction. Thus, extension of the PEG catheter 20 issuppressed when the PEG catheter 20 is pulled with a guide wire 40retained in the tapered member 22. In this case, the filaments 24 neednot be buried and fixed integrally with the thick portion 21 a but mayalso be arrayed along the surface of the thick portion 21 a. The yarnsof the filaments 24 may also be such wires of stainless steel, forexample, having an external diameter of about 0.2 mm, so that they canbe cut with scissors. The yarns of the filaments 24 may also be cottonyarns.

As shown in FIGS. 4( a)-(c), the hole 22 a, which is formed at theleading end of the tapered member 22 of the PEG catheter 20, has adiameter made large enough to accept the head portion 40 a formed at theleading end of the guide wire 40, so that the guide wire 40 can beinserted from the hole 22 a into the tapered member 22.

This tapered member 22 is provided, on the inner side of itsdiametrically large end portion, with a step portion, on which aconnector 30 is fitted. At this fitted portion, the tapered member 22and the connector 30 are fixed by adhering or welding.

As shown in FIG. 5 and FIG. 6, the connector 30 positioned in thetapered member 22 is made hollow to have a cylindrical hole. Theconnector 30 per se has a generally cylindrical shape.

At the leading end of the connector 30, a retaining member 31 is madeintegral with the connector 30. The retaining member 31 extendsobliquely of the axial direction from the leading end of the connector30 to form a slope 31 a, and turns midway into parallel to the axialdirection to form an upper flat face 31 b.

In the retaining member 31, moreover, there is formed a first narrowergroove 32, which extends from the lower portion of the slope 31 a to thevicinity of the central portion of the upper flat face 31 b. In thisupper flat face 31 b of the retaining member 31, there is also formed asecond wider groove 33, which merges into the first groove 32 and has awidth made large enough to pass the head portion 40 a of the guide wire40 therethrough.

In that upper portion of the inside of the tapered member 22, in whichthe retaining member 31 is to be positioned, there is formed a space 34,which is large enough to pass the head portion 40 a of the guide wire 40therethrough, as shown in FIG. 4.

The intragastric retainer 23 positioned at the trailing end of the PEGcatheter 2 0 is constructed of four finger-shaped members, which areconnected in a cross shape at their leading ends and at their trailingends and can be freely folded to be bent and extended, with the pins 5abutting against the outer side of the root portion, as shown in FIG. 2.

As shown in FIG. 7, for example, the pins 5 are formed into a bifurcatedshape. When the pins 5 are inserted into the bearing holes 4 a, theirtwo branches clamp the surface of the PEG tube 21 of the PEG catheter20. When the PEG catheter 20 is pulled in the direction of the tapermember 22, the pins 5 abut against the outer side face of the rootportion of the intragastric retainer 23 to prevent the PEG catheter 20from moving in the direction of the tapered member 22.

The length of the infection-preventing sheath 1, that is, the totallength of the tubular body 2 and the socket 4, is slightly larger thanthe length of the PEG catheter 20, that is, the total length of thetapered member 22, the PEG tube 21 and the intragastric retainer 23.Moreover, the internal diameter of the tubular body 2 is larger than theexternal diameter of the PEG tube 21 but smaller than the diameter orthe transverse width of the intragastric retainer 23.

Depending on the material to be used for the intragastric retainer 23,the internal diameter of the tubular body 2 may be made larger than thediameter of the intragastric retainer 23. In any event, it is sufficientthat the PEG catheter 20 pass together with the intragastric retainer 23(in the folded state or in the original shape) through the tubular body2 of the infection-preventing sheath 1. Here, a jelly or anotherlubricant may be applied to the inner face of the tubular body 2.

The actions with respect to Embodiment 1 thus constructed are describedbelow. The mode of embodiment to be described is called the “pullmethod”. The PEG method is generally executed by an operator, anendoscopist doctor and one or two nurses.

First of all, as shown in FIG. 8, an endoscope 50 is inserted from themouth 70 of a patient lying on his or her back into a stomach 71, andair is blown through the endoscope 50 into the stomach 71 to expand thestomach 71, thereby bringing the stomach wall and the peritoneum intoclose contact with each other. Then, the portion to be needled isdetermined and sufficiently disinfected, and its vicinity is locallyanesthetized. Next, the skin of the portion to be needled is cut about 1cm, and a sheathed needle 51 is inserted into the cut portion.

This sheathed needle 51 is composed of a circular outer cylinder 52 anda needle 53 having a sharpened leading end. The outer cylinder 52 ismade hollow, and the needle 53 slightly protrudes at its leading endfrom the leading end of the outer cylinder 52. The sharpened leading endof the needle 53 pierces into the abdominal wall, the peritoneum and thestomach wall so far that the leading end portion of the outer cylinder52 penetrates into the abdominal wall, the peritoneum and the stomachwall.

Next, as shown in FIG. 9, the needle 53 is extracted from the outercylinder 52 while leaving the leading end portion of the outer cylinder52 needled from the abdominal wall to the stomach wall. Moreover, theleading end of a snare forceps 50 a is extended from the leading end ofthe endoscope 50 in the stomach 71.

Next, the guide wire 40 having the ball-shaped head portion 40 a at itsleading end is inserted from the outside through the outer cylinder 52into the stomach 71, as shown in FIG. 10.

The leading end portion of the guide wire 40 inserted into the stomach71 is gripped by the snare forceps 50 a and is pulled out to the outsideof the oral cavity until it is ungripped from the snare forceps 50 a. Atthis time, the trailing end of the guide wire 40 is held outside of theouter cylinder 52.

Moreover, the PEG catheter 20 is inserted on the side of the taperedmember 22 from the open side of the socket 4 of the infection-preventingsheath 1 into the tubular body 2 and is sheathed from the tapered member22 of the PEG catheter 20 to the intragastric retainer 23 with theinfection-preventing sheath 1 (as referred to FIG. 1). At themanufacture time or before the operation, the PEG catheter 20 may alsobe sheathed in advance with the infection-preventing sheath 1.

Thus, the leading end of the tapered member 22 is slightly extractedfrom the leading end film 3 of the leading end of the tubular body 2 tothe outside, and the leading end of the guide wire 40 extracted from theoral cavity of the patient is pulled from the hole 22 in the leading endof the tapered member 22 into the tapered member 22. The guide wire 40is retained at its head portion 40 a on the connector 30 of the taperedmember 22. As shown in FIG. 11, moreover, the pins 5 are inserted intothe bearing holes 4 a formed in the socket 4 of the infection-preventingsheath 1 thereby to retain the intragastric retainer 23 in the socket 4.

Shown below are the steps to retain the head portion 40 a of the guidewire 40 and the tapered member 22 of the PEG catheter 20. As the guidewire 40 is inserted from the leading end hole 22 a of the tapered member22 into the tapered member 22, the ball-shaped head portion 40 a at theleading end of the guide wire 40 rides on the slope 31 a of theobliquely arranged retaining member 31 and reaches the inside space 34of the tapered member 22 as shown in FIG. 4( a).

As the guide wire 40 is further inserted, the head portion 40 a of theguide wire 40 drops at the upper flat face 31 b of the retaining member31 into the wider groove 33 and enters the narrower groove 32 as shownin FIG. 4( b).

If the guide wire 40 extending from the abdomen of the patient throughthe outer cylinder 52 to the outside is pulled in this state from theoutside, the head portion 40 a at the leading end portion of the guidewire 40 is retained in the stomach by the tapered member 22 at theleading end of the PEG catheter 20 as shown in FIG. 4( c).

When the guide wire 40 is pulled, the pulling force acts at the portionof the tapered member 22, and the PEG catheter 20 and theinfection-preventing sheath 1 are pulled, while the tapered member 22and the PEG tube 21 are sheathed with the infection-preventing sheath 1,into the stomach 71 through the oral cavity, the larynx, the pharynx andesophagus.

At this time, the hardly extensible filaments 24 are fixed in thelongitudinal direction of the thick outer circumferential portion 21 aof the PEG tube 21. As a result, the PEG catheter 20 is not extended,even if the portion of the tapered member 22 of the PEG catheter 20 ispulled by the guide wire 40.

Thus, as shown in FIG. 12, the tapered member 22 of the PEG catheter 20either abuts against the leading end of the outer cylinder 52 or reachesthe vicinity of the outer cylinder 52. This abutment or reach can alsobe confirmed by using the endoscope. In this state, the intragastricretainer 23 at the trailing end of the PEG catheter 20 and the socket 4at the trailing end of the infection-preventing sheath 1 are stilloutside of the mouth 71 of the patient.

Then, the pins 5 are pulled out from the bearing holes 4 a to releasethe intragastric retainer 23, and the guide wire 40 is further pulledout while extracting the outer cylinder 52 from the stomach wall and theabdominal wall, as shown in FIG. 13. As a result, the tapered member 22connected to the guide wire 40 and the PEG tube 21 connected to thetapered member 22 pass through the leading end film 3 at the leading endof the tubular body 2 and appear in the stomach 71. At the trailing endof the tubular body 2, the flexible intragastric retainer 23 is pulledin the folded sate into the tubular body 2 so that it advances towardthe abdomen. While the guide wire 40 is being thus pulled to the outsideof patient, the socket 4 extracted from the mouth 71 of the patient isgripped by the hand of the endoscopist so that the infection-preventingsheath 1 may not be pulled into the body of the patient. As the guidewire 40 is further pulled, the tapered member 22 and the PEG tube 21 arepulled to the outside through the holes in the stomach wall and theabdominal wall, as shown in FIG. 14.

When the intragastric retainer 23 comes out from the leading end film 3of the tubular body 2 and appears in the stomach 71, it restores itsoriginal shape having the four extended filaments, as shown in FIG. 15,to abut against the stomach wall. This abutment of the intragastricretainer 23 against the stomach wall may be confirmed, if necessary, bythe endoscope 50. After this, the tubular body 2 is extracted from themouth 70 of the patient to the outside.

The PEG tube 21 thus extracted to the outside of the patient's body iscut to a suitable length, and a (not-shown) adapter for injectingnutriments is connected to the cut portion. Moreover, the PEG tube 21 isfixed on the patient's body with a suitable fixing tool, thus ending theoperation of the PEG method.

Thus, the outer surfaces of the guide wire 40 and the tubular body 2having passed through the oral cavity, the larynx and the pharynx may becontaminated with the bacteria sticking to the oral cavity, the larynxand the pharynx. However, the guide wire 40 is pulled out of the body ofthe patient through the outer cylinder 52 so that those portions of thestomach wall and the abdominal wall, which are to be subjected to thegastrostomy, are not contaminated by the guide wire 40. Moreover, thePEG catheter 20 is pushed, while being covered all over with theinfection-preventing sheath 1, through the oral cavity, the pharynx andthe larynx into the stomach and is pulled from the tubular body 2through the leading end film 3 in the stomach, so that the PEG catheter20 is not contaminated with the bacteria. Therefore, the portions forthe gastrostomy are not contaminated with the bacteria, even if thetapered member 22 and the PEG tube 21 contact those portions when theyare pulled out from the body. On the other hand, the tubular body 2having its surface contaminated with the bacteria is extracted from themouth of the patient to the outside, so that the portions for thegastrostomy are not contaminated with the infection-preventing sheath 1including the tubular body 2. As a result, those portions can beprevented in advance from any contamination.

In the push method as well, the PEG catheter 20 sheathed with theinfection-preventing sheath 1 is pushed into the stomach so that theportions for the gastrostomy can be effectively prevented from beingcontaminated with the bacteria.

Moreover, the PEG tube 21 is longitudinally provided with the hardlyextensible filaments 24 for reinforcement. As a result, the PEG catheter20 is not extended, although pulled at the portion of the tapered member22, and it is sufficient at the retaining time that the tapered member22 is retained only once.

Embodiment 2

FIG. 16 is an explanatory view showing an infection-preventing catheterkit for the gastrostomy according to Embodiment 2, and FIG. 17 and FIG.18 are explanatory views for explaining the actions of the kit. In thismode of embodiment, the infection-preventing gastrostomy catheter kid isprovided with a housing sheath 60 for folding and housing theintragastric retainer 23 of the PEG catheter 20 preliminarily in anextended state, so that the intragastric retainer 23 may be able to passthrough the infection-preventing sheath 1.

The remaining constructions are substantially similar to those of thecase of Embodiment 1, and their description is omitted by designatingthe same portions as those of Embodiment 1 by the common referencenumerals.

As shown in FIG. 16, the housing sheath 60 is formed to have a flexibletubular body having an outer diameter slightly smaller than the internaldiameter of the tubular body 2 of the infection-preventing sheath 1.

As shown in FIG. 17 and FIG. 18, the intragastric retainer 23 is housedin advance in the folded and extended state so that it may be able topass in that state through the infection-preventing sheath 1.

The infection-preventing sheath 1 is provided, on the inner wall of itsleading end side, with a hook member 6, which is diametrically reducedto have an internal diameter smaller than that of the tubular body 2.When the intragastric retainer 23 of the PEG catheter 20 comes out ofthe leading end portion of the tubular body 2 of theinfection-preventing sheath 1, the hook member 6 hooks only the housingsheath 60, so that it can pull out only the intragastric retainer 23while leaving the housing sheath 60 in the infection-preventing sheath1.

Below are described the steps for the invention thus constructed. As thepins 5 shown in FIG. 18 are pulled out to extract the PEG catheter 20from the infection-preventing sheath 1 with the guide wire 40, the PEGcatheter 20 is moved toward its leading end portion along the inner wallof the infection-preventing sheath 1. Then, the intragastric retainer 23is moved, while being folded and housed in the housing sheath 60,together with the PEG catheter 20 along the inner wall of theinfection-preventing sheath 1. When the housing sheath 60 comes to theposition of the hook member 6, as shown in FIG. 19, only the housingsheath 60 is hooked by the hook member 6. As a result, the intragastricretainer 23 is pulled out from the leading end portion of theinfection-preventing sheath 1 while leaving the housing sheath 60 in thetubular body 2 of the infection-preventing sheath 1, so that theintragastric retainer 23 restores its original shape in the stomach.

The remaining actions are substantially similar to those of the case ofEmbodiment 1, and their description is omitted.

In the aforementioned case, the hook member 6 is not disposed on theinner wall of the infection-preventing sheath 1, but the housing sheath60 may be extracted together with the intragastric retainer 23 into thestomach, so that the intragastric retainer 23 may be extracted from thehousing sheath 60 by pinching and pulling the thread engaging with thehousing sheath 60, by means of the snare.

Alternatively, the hook member 6 is not either disposed on the innerwall of the infection-preventing sheath 1, but the housing sheath 60 maybe extracted together with the intragastric retainer 23, and theintragastric retainer 23 may then be removed directly from the housingsheath 60 by means of the snare.

In this embodiment, the intragastric retainer 23 is folded and extendedin advance and housed in the housing sheath 60 so that it can passthrough the infection-preventing sheath 1. As a result, the passageresistance in the infection-preventing sheath 1 can be reduced to makethe infection-preventing sheath 1 thinner.

1. An infection-preventing sheath gastrostomy catheter kit comprising: agastrostomy catheter including a flexible, hollow tube reinforced withfilaments, a deformable intragastric retainer positioned at the trailingend of said tube, and a tapered member positioned at the leading end ofsaid tube for retaining the leading end portion of a guide wire insertedfrom the leading end hole thereof; and an infection-preventing sheathincluding a flexible, hollow tubular body, and a socket memberpositioned at the trailing end of said tubular body for retaining saidintragastric retainer, to removably sheathe said gastrostomy catheter.2. An infection-preventing sheath gastrostomy catheter kit comprising: agastrostomy catheter including a flexible, hollow tube reinforced withfilaments, a deformable intragastric retainer positioned at the trailingend of said tube, a tapered member positioned at the leading end of saidtube for retaining the leading end portion of a guide wire inserted fromthe leading end hole thereof, and a housing sheath for deforming andhousing said intragastric retainer; and an infection-preventing sheathincluding a flexible, hollow tubular body, and a socket memberpositioned at the trailing end of said tubular body for retaining saidintragastric retainer, to removably sheathe said gastrostomy catheter.3. An infection-preventing sheath gastrostomy catheter kit according toclaim 2, wherein said infection-preventing sheath further includes ahook member disposed near the leading end portion of its inner wall forhooking said housing sheath.
 4. An infection-preventing sheathgastrostomy catheter kit according to claim 2, wherein said housingsheath is made of a slender, hollow, flexible tubular body.
 5. Aninfection-preventing sheath gastrostomy catheter kit according to claim1 4, wherein the gastrostomy catheter is provided with filaments at itsthick portion.
 6. An infection-preventing sheath gastrostomy catheterkit according to claim 5, wherein said filaments are disposed generallyin parallel with the longitudinal direction of the thick portion of thegastrostomy catheter.
 7. An infection-preventing sheath gastrostomycatheter kit according to claim 6, wherein said filaments are buriedgenerally in parallel with the longitudinal direction of the thickportion of the gastrostomy catheter.
 8. An infection-preventing sheathgastrostomy catheter kit according to claim 5, wherein said filamentsare buried at a predetermined spacing in the circumferential directionof the thick portion of the gastrostomy catheter.
 9. Aninfection-preventing sheath gastrostomy catheter kit according to claim1, wherein said filaments are made of wires of stainless steel.
 10. Aninfection-preventing sheath gastrostomy catheter kit according to claim1, wherein the filaments have an external diameter of about 0.2 mm. 11.An infection-preventing sheath gastrostomy catheter kit according toclaim 1, wherein the intragastric retainer is made foldable anddeformable.